The invention disclosed herein is a machine for rotating articles such as female sanitary pads as they advance along a production line. Oblong sanitary pads are the articles which will be used to demonstrate the structure and function of the new machine, but it should be understood that the machine can be used to turn other articles having any shape also.
Sanitary pads are oblong articles composed of a core of fluid absorbent material captured between a front sheet of fluid permeable material and a back sheet of fluid impermeable material. When the pads are discharged from the output of the pad fabricating machine to a conveyor, they are moving along a path that is coincident with or parallel to their long or longitudinal axis. This is not the proper orientation for transferring the pads to a folder or a stacker which groups them for packaging. The back sheet is rather stiff so the pads are folded before being packaged with the soft front sheet areas overlaying and with the stiffer back sheet on the outside. Folding oppositely would result in the stiffer back sheet bunching up or wrinkling which is undesirable.
Before stacks of pads are pushed into cartons or bags in a packaging machine, it is common practice to fold them to form two or three layers and encapsulate them in individual packages. This allows the user to remove one wrapped pad at a time from the carton and carry it in a purse, for instance, for use when occasion arises. Prefolding results in the pad being shortened and made more compact to make it easier to carry in a purse. Folding machines are so designed that it is necessary to convey the pads to the input of the machine while their long dimension is transverse to the direction in which they are moving on the conveyor to facilitate folding. The machine combination described herein rotates the pads 90.degree. about an axis which is perpendicular to the center of the pad.
Two different kinds of pad turning machines are described in U.S. Pat. Nos. 4,619,357 and 4,751,997, respectively, which are assigned to the assignee of the present invention. The pad turning machine described herein is adapted for higher production rates than could be achieved with the machines described in the patents.